pierrejoubert73

How to add a collapsible section in markdown

1. Example

Click me

Heading

1. Foo
2. Bar
   • Baz

• Qux

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

shortjared

a4b.amazonaws.com
access-analyzer.amazonaws.com
account.amazonaws.com
acm-pca.amazonaws.com
acm.amazonaws.com
airflow-env.amazonaws.com
airflow.amazonaws.com
alexa-appkit.amazon.com
alexa-connectedhome.amazon.com
amazonmq.amazonaws.com

sebble

#!/bin/bash

USER=${1:-sebble}

STARS=$(curl -sI https://api.github.com/users/$USER/starred?per_page=1|egrep '^Link'|egrep -o 'page=[0-9]+'|tail -1|cut -c6-)
PAGES=$((658/100+1))

echo You have $STARS starred repositories.
echo

mullnerz

The command I use to archive a single website

wget -mpck --html-extension --user-agent="" -e robots=off --wait 1 -P . www.foo.com

Explanation of the parameters used

• -m (Mirror) Turns on mirror-friendly settings like infinite recursion depth, timestamps, etc.

sbyx

blueprint:
  name: Low battery level detection & notification for all battery sensors
  description: Regularly test all sensors with 'battery' device-class for crossing
    a certain battery level threshold and if so execute an action.
  domain: automation
  input:
    threshold:
      name: Battery warning level threshold
      description: Battery sensors below threshold are assumed to be low-battery (as
        well as binary battery sensors with value 'on').

dusenberrymw

Quick cheat sheet of helpful tmux commands

1. tmux new - Create and attach to a new session.
2. tmux new -s NAME_HERE - Create and attach to a new session named NAME_HERE.
3. CTRL-b, d - Detach (i.e. exit) from the currently-opened tmux session (alternatively, tmux detach). Note, this means press and hold CTRL, press b, release both, press d.
4. tmux ls - Show list of tmux sessions.
5. tmux a - Attach to the previously-opened tmux session.
6. tmux a -t NAME_HERE - Attach to the tmux session named NAME_HERE.
7. CTRL-d - Delete (i.e. kill) currently-opened tmux session (alternatively tmux kill-session).
8. CTRL-b, [ - Enter copy mode, and enable scrolling in currently-opened tmux session. Press q to exit.
9. CTRL-b, " - Split window horizontally (i.e. split and add a pane below).

hubgit

Anonymising PDFs

PDF metadata

Metadata in PDF files can be stored in at least two places:

• the Info Dictionary, a limited set of key/value pairs
• XMP packets, which contain RDF statements expressed as XML

PDF files

ssokolow

/* POSIX paths in JSON via escaping which
doesn't alter valid UTF-8 paths.

The trick is recognizing that JSON can store binary nulls in strings
but nulls are the only character that can't occur in POSIX paths,
so we can use it as an escape character that won't change how existing
serialized paths get interpreted.

Copyright 2018-2020, Stephan Sokolow

pithyless

class Integer
  N_BYTES = [42].pack('i').size
  N_BITS = N_BYTES * 16
  MAX = 2 ** (N_BITS - 2) - 1
  MIN = -MAX - 1
end

p Integer::MAX              #=> 4611686018427387903
p Integer::MAX.class        #=> Fixnum
p (Integer::MAX + 1).class  #=> Bignum